If corporations are getting more rights than individuals, why don't individuals incorporate?
They do if they have the money.
A one-person corporation is little better than a mere human. In the words of one attorney, "If you are a small corp, it will take about fifteen minutes for a large one to get a judge to 'pierce the corporate veil'."
But if you are a large corporation, you can translate money into leverage. A small corporation can sell to the public and get a 5% or 10% return on a $50,000 investment. But a large corporation can invest $50,000 in their Senator and get a 1,000% return on their investment through corporate welfare (after an intermediate step of making bribery legal by redefining it as "soft-money contributions").
For those wealthy enough, corporations are an excellent way of avoiding responsibilities for one's actions. If I put a small amount of poison in my spouse's water, and a couple years later they die and I get a large financial gain, I can go to prison for the crime. But if my corporation can make a large amount of profit putting amall amounts of poison into the water of thousands of people who later die of cancer, I can reap great rewards, but can almost always be shielded from criminal action, since incorporation can turn crimes into mere torts, and transform jail time into mere fines.
It's a great scam if you have the bucks to take advantage of it.